This invention relates to a new and improved waterproof slide type fastener or zipper assembly utilizing interlocking coil or loop type connecting elements.
The ease of manipulation and the relative security of slide type fasteners has led to their widespread use in suits as well as other garments, casings and coverings associated with "in water" and underwater activities. It has been found, however, that such fastener assemblies do not per se seal against the passage of water due to the necessary configuration of their interlocking digit-like connector portions, as well as the holes produced in their connection to supporting tapes. The zipper or slide type fastener assembly has proven to be particularly difficult to economically modify so as to effectively become and stay "waterproof" in its closed condition, particularly after repeated usage.
It has been known in the prior art to form dust covers over slide type fasteners. Such dust covers do not, however, provide a seal against the passage of water. They tend to be readily displaced from their covering position, particularly when in a turbulent water environment.
A slide type fastener has also been known and developed wherein a two-part overlay forms a seal by reason of interlocking edges. While this concept has been applied to specialized equipment, it is not an economical solution to the problem posed and does not make the slide type fastener per se impervious to the passage of water. Embodiments are impractical for general production or wide-spread usage. Moreover, when one has to create a separate cover for a slide type fastener or zipper assembly, there is both an increase in cost and a waste of material. This does not answer the general needs for an inexpensive and easily produced slide type fastener which is capable of affording, in its closed position, a seal against passage of water.